[llvm] [TableGen] Avoid assignmentInAssert warning (PR #139715)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-sie-ubuntu-fast` running on `sie-linux-worker` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/144/builds/25032

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM :: TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td' FAILED ********************
Exit Code: 2

Command Output (stderr):
--
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen -I /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/../../../include -gen-global-isel-combiner      -combiners=MyCombiner -gicombiner-debug-cxxpreds /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td |  /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/FileCheck /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td # RUN: at line 1
+ /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/FileCheck /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td
+ /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen -I /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/../../../include -gen-global-isel-combiner -combiners=MyCombiner -gicombiner-debug-cxxpreds /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td
llvm-tblgen: /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/utils/TableGen/GlobalISelCombinerEmitter.cpp:2615: virtual void {anonymous}::GICombinerEmitter::emitTestSimplePredicate(llvm::raw_ostream&): Assertion `ExpectedID == ID && "combine rules are not ordered!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen -I /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/../../../include -gen-global-isel-combiner -combiners=MyCombiner -gicombiner-debug-cxxpreds /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td
 #0 0x000059bc0a97cb40 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x379b40)
 #1 0x000059bc0a97a11f llvm::sys::RunSignalHandlers() (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x37711f)
 #2 0x000059bc0a97a26a SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #3 0x00007eefc9f5b520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x00007eefc9faf9fc __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 #5 0x00007eefc9faf9fc __pthread_kill_internal ./nptl/pthread_kill.c:78:10
 #6 0x00007eefc9faf9fc pthread_kill ./nptl/pthread_kill.c:89:10
 #7 0x00007eefc9f5b476 gsignal ./signal/../sysdeps/posix/raise.c:27:6
 #8 0x00007eefc9f417f3 abort ./stdlib/abort.c:81:7
 #9 0x00007eefc9f4171b _nl_load_domain ./intl/loadmsgcat.c:1177:9
#10 0x00007eefc9f52e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
#11 0x000059bc0a83f0bb (anonymous namespace)::GICombinerEmitter::emitTestSimplePredicate(llvm::raw_ostream&) GlobalISelCombinerEmitter.cpp:0:0
#12 0x000059bc0a691aa9 llvm::GlobalISelMatchTableExecutorEmitter::emitExecutorImpl(llvm::raw_ostream&, llvm::gi::MatchTable const&, llvm::ArrayRef<llvm::gi::LLTCodeGen>, llvm::ArrayRef<llvm::gi::RuleMatcher>, llvm::ArrayRef<llvm::Record const*>, llvm::ArrayRef<llvm::StringRef>, llvm::StringRef) (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x8eaa9)
#13 0x000059bc0a857e58 EmitGICombiner(llvm::RecordKeeper const&, llvm::raw_ostream&) GlobalISelCombinerEmitter.cpp:0:0
#14 0x000059bc0a9bacbf llvm::TableGen::Emitter::ApplyCallback(llvm::RecordKeeper const&, llvm::raw_ostream&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x3b7cbf)
#15 0x000059bc0a98847d llvm::TableGenMain(char const*, std::function<bool (llvm::raw_ostream&, llvm::RecordKeeper const&)>) (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x38547d)
#16 0x000059bc0a65c208 tblgen_main(int, char**) (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x59208)
#17 0x00007eefc9f42d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16
#18 0x00007eefc9f42e40 call_init ./csu/../csu/libc-start.c:128:20
#19 0x00007eefc9f42e40 __libc_start_main ./csu/../csu/libc-start.c:379:5
#20 0x000059bc0a622b35 _start (/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/llvm-tblgen+0x1fb35)
FileCheck error: '<stdin>' is empty.
FileCheck command line:  /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/bin/FileCheck /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/test/TableGen/GlobalISelCombinerEmitter/match-table-patfrag-root.td

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/139715